Studies on the Decay ofGe67

Abstract

The excited levels of ${\mathrm{Ga}}^{67}$ have been investigated from the decay of ${\mathrm{Ge}}^{67}$ with Ge(Li), Si(Li), and standard scintillation counters. $\gamma$ rays of the following energies were observed: 166.5, 360, 558, 576, 661, 710, 720, 728, 828, 900, 915, 981, 1082, 1116, 1283, 1450, 1677, 1509, 1644, 1810, 1837, 2004, 2100, 2170, 2210, 2510, 2559, 2726, 2958, 2991, 3065, and 3157 keV. The half-life of ${\mathrm{Ge}}^{67}$ was measured to be 19±0.3 min. With the help of $\gamma -\gamma$ coincidence studies, a consistent level scheme of ${\mathrm{Ga}}^{67}$ at 166.5, 333, 828, 1082, 1450, 1810, 2170, 2726, 3157, and 3398 keV has been obtained. Three major positron groups with end-point energies of 3.18 MeV (65%), 2.5 MeV (∼25%), and 1.54 MeV (${\mathrm{Ge}}^{67}$. Each group probably consists of more than one component. The results including spin and parity assignments of some of the excited levels of ${\mathrm{Ga}}^{67}$ are discussed. The half-life of the 166-keV level is measured by delayed coincidence to be less than (0.22±0.05) × ${10}^{-9\mathrm{}}$ sec.